Scientists at Texas A&M University cited
parasites and cold temperatures as the likely causes of death for the 63 birds found on Congress Avenue on Jan. 8.
"We did not find any evidence that there was a public health problem, either from a poison or from an infectious disease," said Dr. Lelve Gayle, the executive director of the Texas Veterinary Medical Diagnostic Laboratory.
"These birds were heavily parasitized by multiple species of parasites," Gayle said. "These birds were sick."
Officials had suspected poisoning, and their investigation continues. City Manager Toby Futrell, briefed on the A&M results, said health officials were awaiting test results from other agencies before announcing the cause of death.
"There is no reason to believe the A&M results are not going to be right," she said. "The bottom line is that they have a negative test for poison."
There was no indication the birds were poisoned.
"Normally when you have birds that have been poisoned, you find food in their stomachs," Gayle said. "And we found no food in their stomachs."